Rack systems and packaging for servers

ABSTRACT

A source module includes a server fluid distribution unit and a busbar unit, as well as connectors. In an embodiment, a server fluid distribution unit to be coupled to a rack fluid distribution unit and the one or more server blades for deploying one or more servers. In an embodiment, a busbar unit to be coupled with an alternating current (AC) power distribution unit and the one or more server blades. In an embodiment, the source module is to be coupled to the rack fluid distribution unit to distribute cooling fluid received from a cooling fluid source to the one or more server blades of corresponding server chassis and to extract heat from the one or more servers.

FIELD OF THE INVENTION

Embodiments of the present invention relate generally to the electronicspackaging, server and rack architecture, hardware design. Moreparticularly, embodiments of the invention relate to rack systems andpackaging for high power density servers.

BACKGROUND

Cooling is a prominent factor in a computer system and data centerdesign. The number of high performance electronics components such ashigh performance processors packaged inside servers has steadilyincreased, thereby increasing the amount of heat generated anddissipated during the ordinary operations of the servers. Thereliability of servers used within a data center decreases if theenvironment in which they operate is permitted to increase intemperature over time. Maintaining a proper thermal environment iscritical for normal operations of these servers in data centers, as wellas the server performance and lifetime. It requires more effective andefficient cooling solutions especially in the cases of cooling thesehigh performance servers.

Heat removal is a prominent factor in a computer system and data centerdesign. The number of high performance electronics components such ashigh performance processors packaged inside servers have steadilyincreased, thereby increasing the amount of heat generated anddissipated during the ordinary operations of the servers. Thereliability of servers used within a data center decreases if theenvironment in which they operate is permitted to increase intemperature over time. Maintaining a proper thermal environment iscritical for normal operations of these servers in data centers, as wellas the server performance and lifetime. It requires more effective andefficient heat removal solutions especially in the cases of coolingthese high performance servers.

The previous rack solutions for blade servers are mainly air coolingbased and using a power distribution solution for the power system. Thissolution may not be the most efficient solutions for servers for hyperscale applications.

With the increasing power densities of the electronics components suchas artificial intelligence (AI) chips and accelerators, the serverpackaging densities are increasing as well. This means the server formfactors may be decreased while the power densities increases. This meansthat more than one servers maybe populated in parallel on the rack, suchas 1U2node, 1U×nodes, 4U 4nodes, 4U 8nodes.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are illustrated by way of example and notlimitation in the figures of the accompanying drawings in which likereferences indicate similar elements.

FIG. 1 shows a top view of a rack level system design according to anembodiment of the application.

FIG. 2 shows a top view of a detailed rack level system design accordingto an embodiment of the application.

FIG. 3 shows a source module design according to an embodiment of theapplication.

FIG. 4 shows a side view of system assembly for high power densityservers according to an embodiment of the application.

FIG. 5 shows a side view of system assembly for PSU according to anembodiment of the application.

FIG. 6A shows a rear view of an example rack integrated with sourcemodules according to an embodiment of the application.

FIG. 6B shows a perspective view of an electronic rack according to anembodiment.

FIG. 7 shows an example rack fully integrated with source modulesaccording to an embodiment of the application.

FIG. 8 is a block diagram illustrating an example of an electronic rackaccording to one embodiment.

DETAILED DESCRIPTION

Various embodiments and aspects of the inventions will be described withreference to details discussed below, and the accompanying drawings willillustrate the various embodiments. The following description anddrawings are illustrative of the invention and are not to be construedas limiting the invention. Numerous specific details are described toprovide a thorough understanding of various embodiments of the presentinvention. However, in certain instances, well-known or conventionaldetails are not described in order to provide a concise discussion ofembodiments of the present inventions.

Reference in the specification to “one embodiment” or “an embodiment”means that a particular feature, structure, or characteristic describedin conjunction with the embodiment can be included in at least oneembodiment of the invention. The appearances of the phrase “in oneembodiment” in various places in the specification do not necessarilyall refer to the same embodiment.

The information technology (IT) hardware industry is a critical marketfor many reasons: it plays a crucial role in business competitiveness,service quality and availability, and also plays a significant role inthe infrastructure total cost of ownership (TCO). IT hardware is closelylinked with the profit of an organization. It is one of the corecompetencies of the internet giant, cloud computing service providers,as well as high performance computing and artificial intelligence (AI)computing related business service users and providers who build,operate, compute, store and manage other IT hardware platforms (e.g.,servers) and infrastructures.

The majority of the hyper-scale owners are customizing full-stacks ofthese hardware systems. For instance, in the rapidly growing cloudcomputing business, the performance and cost (both capital cost andoperation cost) of computing and storage hardware systems, clusters andinfrastructure, all require the service providers to create customizedsystems that fit their individual needs the best. These markets requirecontinuous innovation. An efficient system design and operation benefitsthe service providers in multiple aspects in a long term. The key tothis is to develop continuously with more resilience, efficiency,interoperable and cost effective solutions and architectures.

The present disclosure aims to provide a rack system design for bladeservers or high density systems which are populated parallel on a rack.This design aims to propose an advanced rack architecture and system forhigh power density servers, especially for the high power density bladeservers. Further, this design includes the following design requirementsfor solutions to be deployed in hyper scale cloud data centers, such as:enable liquid cooling for high power blade servers; enable multiple rackpower delivery design; enable central power distribution architectedusing busbar; accommodate existing data center cooling and powerarchitectures; ease of implementations; high reliability; modular designto accommodate different blade server configurations; high scalability;and full serviceability of the entire solution.

The present application includes a rack main unit which is used fordeploying the high power density servers. In an embodiment, the powerdistribution unit is also designed in the similar manner as high powerdensity servers. For example, the individual servers include powerconnection clip and fluid connectors assembled on the rear side. In anembodiment, a source module (also referred to as a src module) is usedon the rear side of the rack for connecting and distributing both fluidsource and power source to the servers. For example, the source moduleincludes server fluid distribution unit which includes both serverconnectors and rack connectors. In an embodiment, busbar unit isincluded in the source module. Further, for example, the one or moreservers are connected with the source module including the fluidconnectors and power connections. In an embodiment, the rack fluiddistribution unit is designed and used on the rear side of the sourcemodule and an AC power distribution unit is added to the other side ofthe rear side of the source module.

According to one aspect, a source module includes a server fluiddistribution unit and a busbar unit. In an embodiment, a server fluiddistribution unit to be coupled to a rack fluid distribution unit andthe one or more server blades for deploying one or more servers. In anembodiment, a busbar unit to be coupled with an alternating current (AC)power distribution unit and the one or more server blades. In anembodiment, the source module is to be coupled to the rack fluiddistribution unit to distribute cooling fluid received from a coolingfluid source to the one or more server blades of corresponding serverchassis and to extract heat from the one or more servers.

In an embodiment, each of the one or more server blades includes one ormore power connection connectors (e.g., clips) to connect with thebusbar unit. The busbar unit includes a power input connector to connectwith the AC power distribution unit. In an embodiment, the source moduleis to be coupled to the AC power distribution unit connected with an ACsource to distribute AC to a power supply unit (PSU). For example, thePSU includes a controller and a rectifier.

In an embodiment, the PSU is connected with the source module through adirect current (DC) output connector. The AC power distribution unitdistributes the AC to the rectifier. In an embodiment, each of the oneor more servers includes one or more sever fluid connectors to connectwith the server fluid distribution unit.

In an embodiment, the server fluid distribution unit includes one ormore server fluid connectors to connect with the one or more serversthrough the one or more server connectors. The server fluid distributionunit includes a rack connector to connect with the rack fluiddistribution unit. In an embodiment, the rack fluid distribution unitincludes rack fluid connectors to connect with the server fluiddistribution unit through the rack connectors. The server fluiddistribution unit is positioned underneath the busbar unit. A leakdetection unit is positioned at a bottom side of the source module. Therack fluid distribution unit is attached onto the rear side of thesource module. The AC power distribution unit is attached onto the rearside of the source module.

In an embodiment, the AC power distribution unit is on one side of therear side of the source module and the rack fluid distribution unit ison the other side of the rear side of the source module. The serverfluid distribution unit includes a rack connector on a first side facingthe rack fluid distribution unit to connect with the rack fluiddistribution connectors on the rack fluid distribution unit. The serverfluid distribution unit includes one or more server connectors on asecond side facing the one or more servers to connect with the one ormore servers through corresponding one or more sever connectors.

According to another aspect, an electronic rack includes a rack fluiddistribution unit, a power distribution unit (e.g., AC powerdistribution unit), a plurality of server chassis arranged in a stack,each server chassis to receive one or more server blades; and aplurality of source modules corresponding to the plurality of serverchassis and positioned on a rear side of the electronic rack. In anembodiment, each source module may include components similar to thesource module described above.

According to a further aspect, a data center cooling system includes afluid supply line coupled to receive cooling fluid from a cooling fluidsource, a fluid return line coupled to return the cooling fluid to thecooling fluid source, and a fluid return line coupled to return thecooling fluid to the cooling fluid source. Each of the plurality ofelectronic racks comprises a rack fluid distribution unit, a powerdistribution unit (e.g., AC power distribution), a plurality of serverchassis arranged in a stack, each server chassis to receive one or moreserver blades; and a plurality of source modules corresponding to theplurality of server chassis and positioned on a rear side of theelectronic rack. In an embodiment, each source module may be implementedas a source module described above.

FIG. 1 shows a top view of a rack level system design 100 according toan embodiment of the application. In particular, FIG. 1 shows the systemdesign 100 when all components are assembled together. That is, theservers are assembled to the rack 105 and these are all IT units (e.g.,107, 109) including the servers (107 a, 107 b, 107 c) and the PSU (109).In an embodiment, the servers (107 a, 107 b, 107 c) include the fluidconnectors (e.g., 111 a) on the rear side. In an embodiment, the servers(107 a, 107 b, 107 c) include the power connectors (e.g., 113 a) on therear side. The PSU (109) may include DC output connectors (e.g., 115)and AC input port.

In an embodiment, the server blades 107 a, 107 b, 107 c and PSU blade109 can be inserted into the corresponding slots of a server chassis,which can be inserted into racks 105 once they populated to rack 105.For example, source module 101 is the key unit in this design. In anembodiment, source module 101 includes power (e.g., 123) and fluid(e.g., 121) distribution components for distributing and deliveringpower and cooling source to the individual servers (107 a, 107 b, 107c). In an embodiment, the Source module 101 is then connected with arear side assembled rack fluid distribution unit 119 and powerdistribution unit 117 (e.g., AC power distribution), which may bepositioned in a vertical orientation to be connected to and to supportmultiple source modules associated with multiple server chassis.

In an embodiment, the overall design 100 can be understood as that therack fluid distribution unit 119 and the power distribution unit 117vertically distributing the sources (e.g., fluid source, power source)to the multiple source modules 101 and the source modules horizontallydistributes the power and cooling source to individual blade nodes. Itcan be understood as that a two dimensional distribution system for bothcooling and power using the current rack architecture 100. Again, thekey module is the source module 101.

In an embodiment, a server chassis includes one or more server blades107 a, 107 b, 107 c connected with a source module 101. Source module101 is positioned on a rear side of an electronic rack 105 forconnecting the server chassis 103 for liquid cooling.

In an embodiment, source module 101 includes a server fluid distributionunit 121 to be coupled to a rack fluid distribution unit 119 and the oneor more server blades 107 a, 107 b, 107 c for deploying one or moreservers. For example, the rack fluid distribution unit can be either arack unit pre-mounted with the rack, or a unit post attached to therack.

In an embodiment, a busbar unit 123 to be coupled with powerdistribution unit 117 and the one or more server blades 107 a, 107 b,107 c. Power distribution unit 117 may be configured to distribute ACpower or DC power dependent upon the configuration of rack powerdistribution unit. In an embodiment, the source module 101 is to becoupled to the rack fluid distribution unit 119 to distribute coolingfluid received from a cooling fluid source to the one or more serverblades 107 a, 107 b, 107 c of corresponding server chassis (e.g., 103)and to extract heat from the one or more servers.

In an embodiment, a source module can be mounted on an electronic rackand includes a rack interface connected to rack manifolds via flexiblehoses. The server side, the source module includes various serverinterfaces, such as blind mated dripless connectors, which can be usedto connect with the cooling devices of server blades of a serverchassis.

The cooling fluid is supplied to the cooling devices of a server bladevia the server supply manifold of the corresponding source module. Acooling device can be a cold plate attached to an electronic device(e.g., a processor) to extract the heat generated from the electronicdevice. The cooling fluid carrying the extracted heat then exits thecooling devices of the server blade into the server return manifold ofthe source module.

FIG. 2 shows a top view of a detailed rack level system design 200according to an embodiment of the application. In particular, FIG. 2provides a more detailed representation of the solution design 200 ineach of the modules. For example, the servers 107 a 107 b, 107 c areintegrated to the racks 105 are blade nodes. In an embodiment, the PSU109 is also designed and populated with the same manner.

In an embodiment, the source module 101 is the key unit used proposed inthe architecture. For example, the design 200 includes a horizontaldistribution unit (i.e., a server fluid distribution unit) 121 and thebusbar unit 123 which are mainly for distributing the power sources. Inan embodiment, the two units (121, 123) are designed to have the busbarunit 123 on top of the distribution unit 121. The actual relativeposition in each dimension can be different. The horizontal distributionunit 121 includes connectors (111 b, 201) on both sides. For example, onone side, which is facing the servers 107, are the server fluidconnectors (e.g., 111 a). These connectors (e.g., 111 a) are used forconnecting with the ones on the servers 107. The rack fluid connectors201 is on the other side.

In an embodiment, a rack fluid vertical distribution unit 119 isattached onto the rear side of the source module 101. For example, therack fluid connectors (e.g., 201) are on the rack fluid verticaldistribution unit 119 and designed to be connected with the rackconnectors 207 in the source module 101. The power distribution unit 117is attached onto the source module 101 or integrated to the rear side ofthe rack 105 which is used for connecting to the facility AC source anddistributing AC to each PSU 109. In an embodiment, the output busbarconnector 115 on the PSU connects to the individual busbar in the sourcemodule 101. The input connectors 205 on the AC distribution unit 117 areused to plug into the PSU AC input 203. It needs to be mentioned thatthe 119 and 117 are extended to the exterior of the rack, this is forillustration purpose. These two unit will be included within the rackonce fully attached to the rack and connected with the source module.

In an embodiment, each of the one or more server blades 107 a, 107 b,107 c includes one or more power connectors or connection clips (e.g.,113 a) to connect with the busbar unit 123. In an embodiment, the busbarunit 123 includes a power input connector 205 to connect with the powerdistribution unit 117. In an embodiment, the source module 101 is to becoupled to the power distribution unit 117 connected with a power sourcesuch as an AC source 203 to distribute power to a power supply unit(PSU) 109.

In an embodiment, the rack fluid distribution unit 119 is attached ontothe rear side of the source module 101. The power distribution unit 117is attached onto the rear side of the source module 101. The powerdistribution unit 117 is on one side of the rear side of the sourcemodule 101 and the rack fluid distribution unit 119 is on the other sideof the rear side of the source module 101. In an embodiment, the serverfluid distribution unit 121 includes a rack fluid connector 201 on afirst side facing the rack fluid distribution unit 119 to connect withthe rack fluid distribution unit 119. In an embodiment, the server fluiddistribution unit 119 includes one or more server connectors 111 a on asecond side facing the one or more servers 107 to connect with the oneor more servers 107 through corresponding one or more sever fluidconnectors 111 a, 111 b. FIG. 3 shows a source module design 300according to an embodiment of the application. In particular, FIG. 3shows the source module design 300 and it can be seen that the key unitspackaged are busbar 123 and horizontal distribution unit 121. In anembodiment, the distribution unit 121 includes connectors 111, 201 onboth sides to connect with different hardware. In an embodiment, thebottom of the module 101 is fully contained to provide a fullsegregation of the full module with the others. In an embodiment, thebusbar 123 is on top of the distribution unit 121 in one design 300.This enables more concept module designs to be developed.

In an embodiment, the rack connectors 207 is the connector forconnecting with the rack fluid connectors 201 (in FIG. 2 ) on the rackfluid distribution unit 119. For example, the rack connectors 207 may bepackaged on different sides on the server fluid distribution unit 121.In an embodiment, server connectors 111 are packaged on the side facingthe front where the servers being inserted.

In an embodiment, the leak detection unit can be added to the bottomside of the source module 101 for providing reliability and monitoringenhancement of the fluid system.

In an embodiment, the server fluid distribution unit 121 is positionedunderneath the busbar unit 123. In an embodiment, a leak detection unitis positioned at a bottom side of the source module 101.

FIG. 4 shows a side view of system assembly 400 for high power densityservers according to an embodiment of the application. In particular,FIG. 4 shows the system detailed function and assembly. For example, theservers 401 a, 401 b are populated to the rack and connected with theirrespective source modules such as source module 101. In an embodiment,the top portions are the power connections 113 a and the bottom portionsare the fluid connections 111 a. In an embodiment, the power connectionincludes the power clip 113 a connecting with the busbar. In anembodiment, the fluid connection includes server connector 111 a andserver fluid connector 111 b connection. In an embodiment, on the otherside of the source module 101 is the connections with the rack verticaldistribution unit 119. In an embodiment, the vertical distribution unit119 is connecting with the horizontal distribution unit 121 in thesource module 101 through the connections the rack connector I and II(e.g., 201).

Although there are two server chassis as shown, more server chassis canbe mounted in an electronic rack. Each server chassis includes multipleslots to receive respective server blades. Each server blade includeselectronic devices mounted on a motherboard, such as, for example, aprocessor, memory, peripheral devices, etc., representing one or moreservers. At least some of the electronic devices, when operate, generateheat. Such heat generating devices may be attached to a cooling devicesuch as a cold plate, which may be coupled to a source module mountednear the rear end of the server blade for liquid cooling as describedabove.

FIG. 5 shows a side view of system assembly 500 for PSU according to anembodiment of the application. In particular, FIG. 5 shows the operationof the PSU 501. In an embodiment, the PSU 501 includes controller 505,rectifiers 503 inside and the PSU 501 is connected to the source module101 a, 101 b through the DC output connectors, and there are multiple DCoutput connectors which means the PSU may be designed for servingseveral source modules 101 a, 101 b. In addition, in an embodiment, theinput connectors 205 are the ones from the AC distribution unit 117 fordistributing the AC source to the PSU 501 and the individual rectifiers503.

In an embodiment, the power distribution unit 117 includes the inputconnectors 205 to be connected with the PSU input 123 and the AC inputplug to be connected with the system AC input source. In an embodiment,the PSU 501 includes a controller 505 and a rectifier 503. In anembodiment, the PSU 501 is connected with the source module 101 througha DC output connector. In an embodiment, the AC power distribution unit117 distributes the AC to the rectifier 503.

FIG. 6A shows an example rack 600 integrated with source modules 101 a,101 b according to an embodiment of the application. In particular, FIG.6B shows the rear side of the rack 105 when the sources modules 101 a,101 b are assembled to the rack 105. In an embodiment, the individualsource module 101 a, 101 b includes the key source distribution hardwareand there are multiple such units used on the rack 105. In anembodiment, the source module 101 a, 101 b can be dynamically changedand different configurations can be used and coexist on a rack 105 basedon the actual based system designs. The sizes and numbers can beflexible configured depending on the servers the rack will be receiving.The rack side design including the vertical fluid and AC source are keptthe same.

FIG. 6B shows a perspective view of a system according to an embodimentof the application. In particular, FIG. 6B shows that a rack ispopulated with several groups of blade servers (601 a, 601 b, 601 c)connected with their respective source modules (603 a, 603 b, 603 c). Inan embodiment, each group of blade servers (601 a, 601 b, 601 c) isfunctioning with a respective source module. In an embodiment, the rackmounted fluid liquid supply and main return are added to the rear sideof the racks once the source modules (603 a, 603 b, 603 c) arepopulated. In an embodiment, the detailed operation may enable the bladeservers (601 a, 601 b, 601 c) to be installed and uninstalled from therack without any impact on other systems.

In addition, a source module can be individually installed anduninstalled without any impact on the rack liquid supply and mainreturn, since the connections are through flexible hoses. In anembodiment, the design enables an efficient control strategy on thefluid system since each of the individual source modules is separatelycontrolled. In an embodiment, even though multiple source modules aresharing the rack liquid supply and main return manifolds, the individualcontroller (not shown) as well as the corresponding sensors input allowsa robust localized control for groups of blade servers.

FIG. 7 shows an example rack 105 fully integrated with source modulesaccording to an embodiment of the application. In particular, FIG. 7shows the rack design 700 with the full solution integrated. Forexample, the rack 105 is not fully populated, and several servers (e.g.,107 a) are populated. In an embodiment, several source modules areassembled onto the rack 105 and both the rack fluid distribution unit119 and distribution unit 117 are integrated. In an embodiment, the topof the two distribution units is connected to the main facility source,cooling fluid system 121 and the AC power bus 123. In an embodiment, thesource module receives the source (e.g., cooling liquid source) from thevertical mounted units 117, 119 and then horizontally distributes(through 121, 123) to the individual servers (e.g., 107 a).

The current design 700 enables to operate all the power and coolinghardware and source from the rear side and it enables an efficientmanner for distributing both cooling fluid source and AC source acrossthe entire rack 105.

In an embodiment, each of the one or more servers 107 a includes one ormore sever fluid connectors 111 a to connect with the server fluiddistribution unit 121. In an embodiment, the server fluid distributionunit 121 includes a rack fluid connector 201 to connect with the rackfluid distribution unit 119.

FIG. 8 is block diagram illustrating an electronic rack according to oneembodiment. Electronic rack 1200 may represent any of the electronicracks as described throughout this application. According to oneembodiment, electronic rack 1200 includes, but is not limited to, heatexchanger 1211, rack management unit (RMU) 1202, and one or more serverchassis 1203A-1203E (collectively referred to as server chassis 1203).Server chassis 1203 can be inserted into an array of server slots (e.g.,standard shelves) respectively from frontend 1204 or backend 1205 ofelectronic rack 1200. Each server chassis includes multiple blade slotsto receive server blades. Each server blade includes server componentsrepresenting one or more servers therein. Each of the server blade, wheninserted, is coupled to a source module mounted on the rack near thebackend of the server chassis and rack. The source module is thencoupled to rack manifolds and the rack power distribution unit, asdescribed above.

Note that although there are five server chassis 1203A-1203E shown here,more or fewer server chassis may be maintained within electronic rack1200. Also note that the particular positions of heat exchanger 1211,RMU 1202, and/or server chassis 1203 are shown for the purpose ofillustration only; other arrangements or configurations of heatexchanger 1211, RMU 1202, and/or server chassis 1203 may also beimplemented. In one embodiment, electronic rack 1200 can be either opento the environment or partially contained by a rack container, as longas the cooling fans can generate airflows from the frontend to thebackend.

In addition, for at least some of the server chassis 1203, an optionalfan module (not shown) is associated with the server chassis. Each ofthe fan modules includes one or more cooling fans. The fan modules maybe mounted on the backend of server chassis 1203 or on the electronicrack to generate airflows flowing from frontend 1204, traveling throughthe air space of the server chassis 1203, and exiting at backend 1205 ofelectronic rack 1200.

In one embodiment, heat exchanger 1211 may be a liquid-to-liquid heatexchanger. Heat exchanger 1211 includes a first loop with inlet andoutlet ports having a first pair of liquid connectors coupled toexternal liquid supply/return lines 1231-1232 to form a primary loop.The connectors coupled to the external liquid supply/return lines1231-1232 may be disposed or mounted on backend 1205 of electronic rack1200. The liquid supply/return lines 1231-1232, also referred to as roomliquid supply/return lines, may be coupled to an external coolingsystem.

In addition, heat exchanger 1211 further includes a second loop with twoports having a second pair of liquid connectors coupled to rack manifold1225 to form a secondary loop, which may include a supply manifold (alsoreferred to as a rack liquid supply line or rack supply manifold) tosupply cooling liquid to server chassis 1203 and a return manifold (alsoreferred to as a rack liquid return line or rack return manifold) toreturn warmer liquid back to heat exchanger 1211. Note that heatexchanger 1211 can be any kind of heat exchangers commercially availableor customized ones. Thus, the details of heat exchanger 1211 will not bedescribed herein.

Each of server chassis 1203 may include one or more informationtechnology (IT) components (e.g., electronic devices such as processors,memory, and/or storage devices). In one embodiment, in at least some ofthe server chassis 1203, an electronic device may be attached to a coldplate. The cold plate includes a liquid distribution channel to receivecooling liquid from the rack liquid supply line of rack manifold 1225.The cooling liquid performs heat exchange from the heat generated fromthe electronic device attached thereon. The cooling liquid carrying theexchanged heat is returned to the rack liquid return line of rackmanifold 1225 and back to heat exchangers 1211.

In another embodiment, some of the server chassis 1203 may include animmersion tank containing immersion cooling liquid therein. Theelectronic devices of the corresponding server(s) are at least partiallysubmerged into the immersion cooling liquid. The immersion coolingliquid may be dielectric cooling fluid, which may be circulated betweenthe immersion tanks and heat exchanger 1211. The cooling liquid may be asingle-phase cooling liquid or two-phase cooling liquid (also referredto as phase-change cooling liquid). The two-phase cooling liquidevaporates from a liquid form into a vapor form when the temperature ofthe cooling liquid is above a predetermined temperature threshold (e.g.,the boiling point of the cooling liquid). The vapor flows upstream viathe vapor line from the corresponding server chassis to heat exchanger1211. Heat exchanger 1211 may include a condenser to condense the vaporfrom the vapor form back to the liquid form, where the cooling liquid isthen supplied back to the server chassis.

Note that some of the server chassis 1203 may be configured withsingle-phase liquid cooling, while other server chassis may beconfigured with two-phase liquid cooling. Even within a single serverchassis, some of the IT components may be configured with single-phaseliquid cooling, while other IT components may be configured withtwo-phase liquid cooling. Rack manifold 1225 may include a first rackmanifold for single-phase cooling and a second rack manifold fortwo-phase cooling to be coupled to the same or different server chassisfor different types of cooling. Some of the server chassis 1203 may beconfigured with regular liquid and air cooling, while other serverchassis may be configured with immersion cooling.

Some of the IT components may perform data processing tasks, where theIT components may include software installed in a machine-readablemedium such as a storage device, loaded into a memory, and executed byone or more processors to perform the data processing tasks. Serverchassis 1203 may include a host server (referred to as a host node)coupled to one or more compute servers (also referred to as computingnodes). The host server (having one or more central processing units orCPUs) typically interfaces with clients over a network (e.g., Internet)to receive a request for a particular service such as storage services(e.g., cloud-based storage services such as backup and/or restoration),executing an application to perform certain operations (e.g., imageprocessing, deep data learning algorithms or modeling, etc., as a partof a software-as-a-service or SaaS platform). In response to therequest, the host server distributes the tasks to one or more of thecomputing nodes or compute servers (having one or more graphics/generalprocessing units or GPUs) managed by the host server. The computeservers perform the actual tasks, which may generate heat during theoperations.

Electronic rack 1200 further includes optional RMU 1202 configured toprovide and manage power supplied to servers 1203 and heat exchanger1211. RMU 1202 may be coupled to a power supply unit (not shown) tomanage the power consumption of the power supply unit. The power supplyunit may include the necessary circuitry (e.g., an AC to DC or DC to DCpower converter, battery, transformer, or regulator, etc.,) to providepower to at least some of the remaining components of electronic rack1200.

In one embodiment, RMU 1202 includes optional optimization module 1221and rack management controller (RMC) 1222. RMC 1222 may include amonitor to monitor operating status of various components withinelectronic rack 1200, such as, for example, computing nodes 1203, heatexchanger 1211, and the fan modules. Specifically, the monitor receivesoperating data from various sensors representing the operatingenvironments of electronic rack 1200. For example, the monitor mayreceive operating data representing temperatures of the processors,cooling liquid, and airflows, which may be captured and collected viavarious temperature sensors. The monitor may also receive datarepresenting the fan power and pump power generated by one or more fanmodules and liquid pumps, which may be proportional to their respectivespeeds. These operating data are referred to as real-time operatingdata. Note that the monitor may be implemented as a separate modulewithin RMU 1202.

Based on the operating data, optimization module 1221 performs anoptimization using a predetermined optimization function or optimizationmodel to derive a set of optimal fan speeds for the fan modules and anoptimal pump speed for a liquid pump, such that the total powerconsumption of the liquid pump and the fan modules reaches minimum,while the operating data associated with the liquid pump and coolingfans of the fan modules are within their respective designedspecifications. Once the optimal pump speed and optimal fan speeds havebeen determined, RMC 1222 configures the liquid pump and cooling fans ofthe fan modules based on the optimal pump speeds and fan speeds.

In the foregoing specification, embodiments of the invention have beendescribed with reference to specific exemplary embodiments thereof. Itwill be evident that various modifications may be made thereto withoutdeparting from the broader spirit and scope of the invention as setforth in the following claims. The specification and drawings are,accordingly, to be regarded in an illustrative sense rather than arestrictive sense.

What is claimed is:
 1. A source module positioned on a rear side of anelectronic rack for connecting a server chassis for liquid cooling,comprising: a server fluid distribution unit to be coupled to a rackfluid distribution unit and one or more server blades of a serverchassis, the server fluid distribution unit including a server supplymanifold to receive cooling fluid from a rack fluid distribution unitand to distribute the cooling fluid to the server blades, and a serverreturn manifold to receive the cooling fluid from the server blades andto return the cooling fluid to the rack fluid distribution unit; and abusbar unit to be coupled with a power distribution unit and the one ormore server blades, the busbar unit including a rack power interface tobe coupled to the power distribution unit to receive power, and aplurality of server power interfaces to distribute the power to one ormore servers.
 2. The source module of claim 1, wherein the server fluidsupply manifold comprises a rack supply connector to be connected to therack fluid distribution unit and one or more server supply connectors tobe connected to the server blades, and wherein the server fluid returnmanifold comprises a rack return connector to be connected to the rackfluid distribution unit and one or more server return connectors to beconnected to the server blades.
 3. The source module of claim 1, whereinthe server fluid supply manifold and the server fluid return manifoldare position horizontally.
 4. The source module of claim 1, wherein thesource module is to be coupled to the power distribution unit connectedwith a power source to distribute the power to a power supply unit (PSU)contained within the server chassis.
 5. The source module of claim 4,wherein the PSU is connected with the source module through a directcurrent (DC) output connector.
 6. The source module of claim 1, whereinthe server fluid distribution unit is positioned underneath the busbarunit.
 7. The source module of claim 1, further comprising a leakdetection unit positioned at a bottom side of the source module.
 8. Thesource module of claim 1, wherein the rack fluid distribution unit isattached onto the rear side of the source module.
 9. The source moduleof claim 1, wherein the power distribution unit is attached onto therear side of the source module.
 10. The source module of claim 1,wherein the power distribution unit is on one side of the rear side ofthe source module and the rack fluid distribution unit is on the otherside of the rear side of the source module.
 11. An electronic rack,comprising: a rack fluid distribution unit; a power distribution unit; aplurality of server chassis arranged in a stack, each server chassis toreceive one or more server blades; and a plurality of source modulescorresponding to the plurality of server chassis and positioned on arear side of the electronic rack, each source module comprising: aserver fluid distribution unit to be coupled to a rack fluiddistribution unit and one or more server blades of a server chassis, theserver fluid distribution unit including a server supply manifold toreceive cooling fluid from the rack fluid distribution unit and todistribute the cooling fluid to the server blades, and a server returnmanifold to receive the cooling fluid from the server blades and toreturn the cooling fluid to the rack fluid distribution unit; and abusbar unit to be coupled with a power distribution unit and the one ormore server blades, the busbar unit including a rack power interface tobe coupled to the power distribution unit to receive power, and aplurality of server power interfaces to distribute the power to one ormore servers.
 12. The electronic rack of claim 11, wherein the serverfluid supply manifold comprises a rack supply connector to be connectedto the rack fluid distribution unit and one or more server supplyconnectors to be connected to the server blades, and wherein the serverfluid return manifold comprises a rack return connector to be connectedto the rack fluid distribution unit and one or more server returnconnectors to be connected to the server blades.
 13. The electronic rackof claim 11, wherein the server fluid supply manifold and the serverfluid return manifold are position horizontally.
 14. The electronic rackof claim 11, wherein the source module is to be coupled to the powerdistribution unit connected with a power source to distribute the powerto a power supply unit (PSU) contained within the server chassis. 15.The electronic rack of claim 14, wherein the PSU is connected with thesource module through a direct current (DC) output connector.
 16. Theelectronic rack of claim 11, wherein the power source delivered to thepower distribution unit is an AC power source.
 17. The electronic rackof claim 11, wherein the power source delivered to the powerdistribution unit is a renewable power source.
 18. The electronic rackof claim 11, wherein the server fluid distribution unit is positionedunderneath the busbar unit.
 19. The electronic rack of claim 11, whereineach source module further comprises a leak detection unit positioned ata bottom side of the source module.
 20. A data center cooling system,comprising: a fluid supply line coupled to receive cooling fluid from acooling fluid source; a fluid return line coupled to return the coolingfluid to the cooling fluid source; and a plurality of electronic rackscoupled to the fluid supply line and the fluid return line, wherein eachof the plurality of electronic racks comprises: a rack fluiddistribution unit; a power distribution unit; a plurality of serverchassis arranged in a stack, each server chassis to receive one or moreserver blades; and a plurality of source modules corresponding to theplurality of server chassis and positioned on a rear side of anelectronic rack, each source module comprising: a server fluiddistribution unit to be coupled to a rack fluid distribution unit andone or more server blades of a server chassis, the server fluiddistribution unit including a server supply manifold to receive coolingfluid from the rack fluid distribution unit and to distribute thecooling fluid to the server blades, and a server return manifold toreceive the cooling fluid from the server blades and to return thecooling fluid to the rack fluid distribution unit; and a busbar unit tobe coupled with a power distribution unit and the one or more serverblades, the busbar unit including a rack power interface to be coupledto the power distribution unit to receive power, and a plurality ofserver power interfaces to distribute the power to the one or moreservers.